Field of the Invention
The present invention relates to blades and vanes for an axial flow compressor used in mechanical equipments such as, for example, gas turbine engine, and a method of manufacturing the blades and vanes.
Description of Related Art
The axial flow compressor is operable to continuously compress a gaseous medium with the utilization of the pressure difference developed between upstream and downstream sides of a rotating blade and a static vane. As compared with a centrifugal compressor designed to accomplish the same object, the axial flow compressor can handle the large flow rate, can be downsized to have a small diameter, and can be expected to exhibit the performance with high compressibility rate and high efficiency. On the other hand, the axial flow compressor is complicated in mechanical structure and makes use of a number of component parts and is hence necessarily expensive. Such an axial flow compressor is employed in various applications, for example, an aircraft gas turbine engine (jet engine), a gas turbine engine for a high speed marine vessel or an electric generator, a gas-flow separating device, a dust collector, a vacuum pump, a wind tunnel, a propane (natural gas) oxidative dehydrogenization device, a pipeline gas compressor and so on.
In the axial flow compressor of a relatively large size such as, for example, the gas turbine engine, an axial flow compressor blade unit such as a rotating blade (rotor), which is rotatable at a high speed, and/or a static vane (stator), which does not rotate, is employed. The axial flow compressor blade unit is generally comprised of an airfoil section and a platform section. In these blade component parts, the airfoil section has an aerodynamic shape, which is exclusively designed to meet with the complicated geometrical requirements, and the platform section has couplings required to be fitted to a rotary disk or shaft and a casing, and the axial flow compressor blade is in general designed and configured to have a complicated shape. Accordingly, the patent document 1 listed below discloses the manufacture of such blade components, in which they are first forged or cast to have a basic blade component shape and then go through various machining processing steps to make the blade components to have final blade component shapes and sizes. Also, the patent document 2 listed blow discloses a method of shaping the airfoil section with the use of a five axis milling machine or a precision forging.